Ion beam systems are used, for example, to manufacture or modify structures of objects by removing material from the object or depositing material on the object using an ion beam. The removal of material from the object and the depositing of material on the object may involve supplying of a process gas to the object, wherein the process gas is activated using the ion beam.
Ion beam systems can be further used for generating an image of an object by scanning an ion beam across the object and detecting charged particles or other radiation emerging from the object due to the incidence of the ion beam. Intensities of the detected particles or radiation provide the image information similar to methods used for obtaining images of an object using a scanning electron microscope.
A conventional ion beam system comprises an ion beam source for generating an ion beam, an acceleration electrode for accelerating ions of the ion beam to an adjustable kinetic energy, and a beam deflector for directing the ion beam to a desired location on the object. The beam deflector comprises plural pairs of deflection electrodes distributed in a circumferential direction about the ion beam, wherein adjustable electric voltages can be applied to the pairs of deflection electrodes in order to generate an adjustable electric deflection field between the pairs of deflection electrodes resulting in the desired deflection of the ion beam.
It has been found that an accuracy of achieving a desired deflection of the beam can be insufficient, in particular if kinetic energies of the ions of the ion beam are low and/or if the desired amounts of deflection change rapidly.